This Project of this Clinical Research Center has been concerned with issues of diagnosis and course of language impairment among children who were initially identified in kindergarten. Our objectives during the last funding period concerned issues of stability of and recovery from language impairment investigated different diagnostic systems and standards for diagnosis. Three approaches to the measurement and diagnosis of language impairment have been employed. One approach has used traditional psychometric measures of spoken language comprehension and production. This will be contrasted with two other diagnostic approaches that have very different theoretical bases. One measure is based upon obligatory tense usage and is motivated by contemporary linguistic theory. The other derives from cognitive psychology and uses a non-work repetition task to measure phonological or working memory. Despite their theoretical differences, each of these two alternative approaches has been shown to be sensitive to language impairment. These different measurement approaches have been and will continue to be used to describe the course of language impairment during the school years. Using these measures, this project will be concerned with the extent to which language impairments may resolve by adolescence or alternatively remain stable. Individual differences in recovery or persistence of language impairment will be identified and predictors of these differences will be evaluated. The language measures and diagnoses obtained from this project will also serve as variables for Projects by Leonard and Catts.